"I gotta ask you, everyone wants to know, are you and Jen getting back?" the photographer asked, before Pitt laughed and said: "Oh my god...All right, have a good one."

Sounds like a pretty cut-and-dry dismissal.

A source added to ET that Aniston and Pitt, who are both single, have remained friends in the years since their marriage ended, so Pitt's attendance at Aniston's party shouldn't have come as a surprise.

"Jen and Brad have remained friends and have spoken with each other quite a few times since they both became single. They are friends and have supported each other through some tough times," the source said. "They've come so far since their marriage and plan to stay friends for life. There are truly no hard feelings between them."